The World Wide Web Consortium and the Unicode Consortium have released a joint draft called "Unicode in XML and Other Markup Languages". The document addresses the problem created by certain characters: While there may be valid reasons to support these characters and their specifications in plain text, their use in marked-up text can conflict with the rules of the markup language.

Such characters include for example the line and paragraph separators, which obviously have their equivalent in markup languages, ie. br and p in HTML.

In related news, John Cowan announced his ongoing independent development of a corrigendum to XML 1.0 intended to bring it into sync with Unicode 3.0.